Block freeing thread should call Region::destroy instead of delete
https://bugs.webkit.org/show_bug.cgi?id=114544

Reviewed by Oliver Hunt.

Since Region doesn't have a virtual destructor, calling delete will not properly clean up all of 
the state of the Region. We should call destroy() instead.

* heap/BlockAllocator.cpp:
(JSC::BlockAllocator::releaseFreeRegions):
(JSC::BlockAllocator::blockFreeingThreadMain):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@148314 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Demystify some code in RenderLayer::updateScrollableAreaSet()
https://bugs.webkit.org/show_bug.cgi?id=114543

Reviewed by Tim Horton.

Clean up some code that called functions with important side effects
inside a ternary operator, and clean up the #ifdefs.

* rendering/RenderLayer.cpp:
(WebCore::RenderLayer::updateScrollableAreaSet):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@148316 268f45cc-cd09-0410-ab3c-d52691b4dbfc